Shown here is a MicroDuct distribution box (MDB) in a telecom room, where they typically are housed. MDBs are used at fiber pathway branching locations and accommodate rerouting, MACs, and pathway maintenance | Shown here is a MicroDuct distribution box (MDB) in a telecom room, where they typically are housed. MDBs are used at fiber pathway branching locations and accommodate rerouting, MACs, and pathway maintenance |